Abstract 837: Pathogenesis and progression of esophageal adenocarcinoma by prior diagnosis of Barrett's esophagus

The absolute risk of carcinogenic progression given Barrett's esophagus (BE) is low and a majority of esophageal adenocarcinoma (EA) cases are diagnosed at first endoscopy without having had a prior diagnosis of BE. Therefore the research field has largely utilized case-control study designs with the implicit assumption that each case-group assessed (reflux, BE, EA) is representative of that stage in a linear progression towards cancer. To test the assumption that EA cases are a homogeneous group and therefore research findings may contribute to evidence-based prevention programs for diagnosed BE populations, we conducted a case-case study comparing the clinical presentation, medical history and survival of EA patients with and without a prior diagnosis of BE in the SEER-Medicare database. Eligible EA cases were diagnosed at ages > = 68 years during 1994-2009. Exposures were captured for a 2 year period starting 3 years prior to diagnosis. There were 5,271 EA patients in this study, 87% (n = 4,609) of which lacked a previous diagnosis of BE (“EA-no prior BE”). In univariate case-case comparisons, patient characteristics (age, sex, race, etc.) were mostly similar with the exceptions that EA-prior BE cases had lower comorbidity scores and a higher average number of physician visits. Conversely, tumor and treatment characteristics were starkly different; EA-prior BE cases were typically diagnosed with lower stage, lower grade, smaller tumors, and were less likely to have met...
Source: Cancer Research - Category: Cancer & Oncology Authors: Tags: Epidemiology Source Type: research